From eedce141cd2dad8d0cefc5468ef41898949a7031 Mon Sep 17 00:00:00 2001 From: Thadeu Lima de Souza Cascardo Date: Thu, 25 Oct 2012 13:37:51 -0700 Subject: genalloc: stop crashing the system when destroying a pool The genalloc code uses the bitmap API from include/linux/bitmap.h and lib/bitmap.c, which is based on long values. Both bitmap_set from lib/bitmap.c and bitmap_set_ll, which is the lockless version from genalloc.c, use BITMAP_LAST_WORD_MASK to set the first bits in a long in the bitmap. That one uses (1 << bits) - 1, 0b111, if you are setting the first three bits. This means that the API counts from the least significant bits (LSB from now on) to the MSB. The LSB in the first long is bit 0, then. The same works for the lookup functions. The genalloc code uses longs for the bitmap, as it should. In include/linux/genalloc.h, struct gen_pool_chunk has unsigned long bits[0] as its last member. When allocating the struct, genalloc should reserve enough space for the bitmap. This should be a proper number of longs that can fit the amount of bits in the bitmap. However, genalloc allocates an integer number of bytes that fit the amount of bits, but may not be an integer amount of longs. 9 bytes, for example, could be allocated for 70 bits. This is a problem in itself if the Least Significat Bit in a long is in the byte with the largest address, which happens in Big Endian machines. This means genalloc is not allocating the byte in which it will try to set or check for a bit. This may end up in memory corruption, where genalloc will try to set the bits it has not allocated. In fact, genalloc may not set these bits because it may find them already set, because they were not zeroed since they were not allocated. And that's what causes a BUG when gen_pool_destroy is called and check for any set bits. What really happens is that genalloc uses kmalloc_node with __GFP_ZERO on gen_pool_add_virt. With SLAB and SLUB, this means the whole slab will be cleared, not only the requested bytes. Since struct gen_pool_chunk has a size that is a multiple of 8, and slab sizes are multiples of 8, we get lucky and allocate and clear the right amount of bytes. Hower, this is not the case with SLOB or with older code that did memset after allocating instead of using __GFP_ZERO. So, a simple module as this (running 3.6.0), will cause a crash when rmmod'ed. [root@phantom-lp2 foo]# cat foo.c #include #include #include #include MODULE_LICENSE("GPL"); MODULE_VERSION("0.1"); static struct gen_pool *foo_pool; static __init int foo_init(void) { int ret; foo_pool = gen_pool_create(10, -1); if (!foo_pool) return -ENOMEM; ret = gen_pool_add(foo_pool, 0xa0000000, 32 << 10, -1); if (ret) { gen_pool_destroy(foo_pool); return ret; } return 0; } static __exit void foo_exit(void) { gen_pool_destroy(foo_pool); } module_init(foo_init); module_exit(foo_exit); [root@phantom-lp2 foo]# zcat /proc/config.gz | grep SLOB CONFIG_SLOB=y [root@phantom-lp2 foo]# insmod ./foo.ko [root@phantom-lp2 foo]# rmmod foo ------------[ cut here ]------------ kernel BUG at lib/genalloc.c:243! cpu 0x4: Vector: 700 (Program Check) at [c0000000bb0e7960] pc: c0000000003cb50c: .gen_pool_destroy+0xac/0x110 lr: c0000000003cb4fc: .gen_pool_destroy+0x9c/0x110 sp: c0000000bb0e7be0 msr: 8000000000029032 current = 0xc0000000bb0e0000 paca = 0xc000000006d30e00 softe: 0 irq_happened: 0x01 pid = 13044, comm = rmmod kernel BUG at lib/genalloc.c:243! [c0000000bb0e7ca0] d000000004b00020 .foo_exit+0x20/0x38 [foo] [c0000000bb0e7d20] c0000000000dff98 .SyS_delete_module+0x1a8/0x290 [c0000000bb0e7e30] c0000000000097d4 syscall_exit+0x0/0x94 --- Exception: c00 (System Call) at 000000800753d1a0 SP (fffd0b0e640) is in userspace Signed-off-by: Thadeu Lima de Souza Cascardo Cc: Paul Gortmaker Cc: Benjamin Gaignard Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/genalloc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/genalloc.c b/lib/genalloc.c index ca208a92628c..54920433705a 100644 --- a/lib/genalloc.c +++ b/lib/genalloc.c @@ -178,7 +178,7 @@ int gen_pool_add_virt(struct gen_pool *pool, unsigned long virt, phys_addr_t phy struct gen_pool_chunk *chunk; int nbits = size >> pool->min_alloc_order; int nbytes = sizeof(struct gen_pool_chunk) + - (nbits + BITS_PER_BYTE - 1) / BITS_PER_BYTE; + BITS_TO_LONGS(nbits) * sizeof(long); chunk = kmalloc_node(nbytes, GFP_KERNEL | __GFP_ZERO, nid); if (unlikely(chunk == NULL)) -- cgit v1.2.3 From a3cea9894157c20a5b1ec08b7e0b5f2019740c10 Mon Sep 17 00:00:00 2001 From: Manuel Lauss Date: Thu, 22 Nov 2012 11:58:22 +0100 Subject: MPI: Fix compilation on MIPS with GCC 4.4 and newer Since 4.4 GCC on MIPS no longer recognizes the "h" constraint, leading to this build failure: CC lib/mpi/generic_mpih-mul1.o lib/mpi/generic_mpih-mul1.c: In function 'mpihelp_mul_1': lib/mpi/generic_mpih-mul1.c:50:3: error: impossible constraint in 'asm' This patch updates MPI with the latest umul_ppm implementations for MIPS. Signed-off-by: Manuel Lauss Cc: Linux-MIPS Cc: Dmitry Kasatkin Cc: James Morris Patchwork: https://patchwork.linux-mips.org/patch/4612/ Signed-off-by: Ralf Baechle --- lib/mpi/longlong.h | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/mpi/longlong.h b/lib/mpi/longlong.h index 678ce4f1e124..095ab157a521 100644 --- a/lib/mpi/longlong.h +++ b/lib/mpi/longlong.h @@ -641,7 +641,14 @@ do { \ ************** MIPS ***************** ***************************************/ #if defined(__mips__) && W_TYPE_SIZE == 32 -#if __GNUC__ > 2 || __GNUC_MINOR__ >= 7 +#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 4 +#define umul_ppmm(w1, w0, u, v) \ +do { \ + UDItype __ll = (UDItype)(u) * (v); \ + w1 = __ll >> 32; \ + w0 = __ll; \ +} while (0) +#elif __GNUC__ > 2 || __GNUC_MINOR__ >= 7 #define umul_ppmm(w1, w0, u, v) \ __asm__ ("multu %2,%3" \ : "=l" ((USItype)(w0)), \ @@ -666,7 +673,15 @@ do { \ ************** MIPS/64 ************** ***************************************/ #if (defined(__mips) && __mips >= 3) && W_TYPE_SIZE == 64 -#if __GNUC__ > 2 || __GNUC_MINOR__ >= 7 +#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 4 +#define umul_ppmm(w1, w0, u, v) \ +do { \ + typedef unsigned int __ll_UTItype __attribute__((mode(TI))); \ + __ll_UTItype __ll = (__ll_UTItype)(u) * (v); \ + w1 = __ll >> 64; \ + w0 = __ll; \ +} while (0) +#elif __GNUC__ > 2 || __GNUC_MINOR__ >= 7 #define umul_ppmm(w1, w0, u, v) \ __asm__ ("dmultu %2,%3" \ : "=l" ((UDItype)(w0)), \ -- cgit v1.2.3 From f3537f91f9be2ce5fcbaa1aa6d787ad0436daec6 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 Oct 2012 15:05:55 +0100 Subject: ASN.1: Fix an indefinite length skip error Fix an error in asn1_find_indefinite_length() whereby small definite length elements of size 0x7f are incorrecly classified as non-small. Without this fix, an error will be given as the length of the length will be perceived as being very much greater than the maximum supported size. Signed-off-by: David Howells Signed-off-by: Rusty Russell --- lib/asn1_decoder.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/asn1_decoder.c b/lib/asn1_decoder.c index de2c8b5a715b..5293d2433029 100644 --- a/lib/asn1_decoder.c +++ b/lib/asn1_decoder.c @@ -91,7 +91,7 @@ next_tag: /* Extract the length */ len = data[dp++]; - if (len < 0x7f) { + if (len <= 0x7f) { dp += len; goto next_tag; } -- cgit v1.2.3 From 527897ccd968c86ad3265d62962c8beccdb94e47 Mon Sep 17 00:00:00 2001 From: Tim Gardner Date: Tue, 4 Dec 2012 12:52:28 -0700 Subject: lib/Makefile: Fix oid_registry build dependency It is $(obj)/oid_registry.o that is dependent on $(obj)/oid_registry_data.c. The object file cannot be built until $(obj)/oid_registry_data.c has been generated. A periodic and hard to reproduce parallel build failure is due to this incorrect lib/Makefile dependency. The compile error is completely disingenuous. GEN lib/oid_registry_data.c Compiling 49 OIDs CC lib/oid_registry.o gcc: error: lib/oid_registry.c: No such file or directory gcc: fatal error: no input files compilation terminated. make[3]: *** [lib/oid_registry.o] Error 4 Cc: Andrew Morton Cc: Akinobu Mita Cc: Michel Lespinasse Cc: David Howells Cc: "David S. Miller" Signed-off-by: Tim Gardner Signed-off-by: Rusty Russell --- lib/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/Makefile b/lib/Makefile index 821a16229111..a08b791200f3 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -163,7 +163,7 @@ $(obj)/crc32table.h: $(obj)/gen_crc32table # obj-$(CONFIG_OID_REGISTRY) += oid_registry.o -$(obj)/oid_registry.c: $(obj)/oid_registry_data.c +$(obj)/oid_registry.o: $(obj)/oid_registry_data.c $(obj)/oid_registry_data.c: $(srctree)/include/linux/oid_registry.h \ $(src)/build_OID_registry -- cgit v1.2.3